Method for controlling phytopathogenic fungi using branched aminoalkanephosphonic acids

ABSTRACT

Branched aminoalkanephosphonic acids, i.e. compounds containing at least one alkyl substituent in the αposition to the phosphonic acid group are used for controlling phytopathogenic fungi by applying an effective amount of the compound to seed or foliage.

The present application is a divisional application of Application Ser.No. 07/207,921 filed June 10, 1988, now U.S. Pat. No. 4,888,330, whichis a continuation of Application Ser. No. 06/851,211 filed Apr. 14,1986, now abandoned, which is a continuation-in-part of Application Ser.No. 06/695,227 filed Jan. 28, 1985, now abandoned.

The present invention relates to a method for killing or inhibiting thegrowth of phytopathogenic fungi using certain branchedaminoalkanephosphonic acids. The compounds used according the methodhave been found to be particularly suitable for control of fungaldiseases in plants.

Various biological effects of different aminoalkanephosphonic acidcompounds are previously known. From the U.S. Pat. No. 3,764,677fungicidal effect against phytopathogenic fungi is known for specificesters of a straight chain aminoalkanephosphonic acid, namely diethylbetaaminoethylphosphonate. Allyl and propynyl esters of a straight chainaminoalkanephosphonic acid, aminomethylphosphonic acid, have also beendisclosed as having such an effect. The USSR patent No. 697519 disclosesa process for the preparation of such branched aminoalkanephosphonicacids as are used according to the present invention. In the USSR patentit is alleged that the branched aminoalkanephosphonic acids findapplication as corrosion inhibitors, complexones, antioxidants, and alsoas insecticides or fungicides.

According to the present invention it has been found that certainbranched aminoalkanephosphonic acids are especially useful as fungicidesfor phytopathogenic fungi and can thus be used in agriculture andhorticulture. Branched aminoalkanephosphonic acids herein refers toaminoalkanephosphonic acids which have at least one alkyl substituent inthe α-position to the phosphonic acid group.

According to the present method for controlling phytopathogenic fungithe aminoalkanephosphonic acids are used as seed-dressing agents or asfoliar sprays.

The branched aminoalkanephosphonic acids used in the method of theinvention have the general formula ##STR1## wherein n is 0 or 1; R₁ isan alkyl group having 1 to 12 carbon atoms and R₂ is hydrogen or analkyl group having 1 to 12 carbon atoms.

Branched aminoalkanephosphonic acids used according to the presentinvention can eg be prepared by condensation of alkylcarbamates withaldehydes and triphenylphosphite, as described in Tetrahedron LettersNo. 32, 1977, pages 2823 to 2824. Salts of the acids can be prepared inper se known manners, eg as shown in the examples.

The important feature of the compounds used is the α-substitution to thephosphonic acid group by one or two alkyl groups. The number of carbonatoms in these alkyl groups, R₁ and R₂, should suitably not exceed 8,and preferably not exceed 5. If two branches are present the totalnumber of carbon atoms should suitably not exceed 8 and preferably notexceed 5. Thus the preferred compounds are such containing shortbranches, and particularly such with one short branch. Compounds whereinn is 0 are preferred. It has been found that particularly good effect isobtained with the aminoalkanephosphonic acid 1-aminopropanephosphonicacid, wherein the branch thus is an ethyl group. The compounds can be inthe form of their acid addition salts acceptable to the use. Here saltsof organic acids can be used but the acid addition salts are preferablysalts of mineral acids such as hydrochloric acid, sulphuric acid andphosphoric acid etc.

In the present method for controlling phytopathogenic fungi thecompounds are used as seed-dressing agents or as foliar fungicides,preferably as seed-dressing agents, and they are hereby used in amountseffective to kill or inhibit the growth of the fungi in question, thedosage being decided from desired protection, material to be treated,treatment method etc.

The compounds are soluble in water, the solubility varies depending onstructure and pH, and they can generally be used in the form of waterbased formulations. They can also be used in formulations withconventional carriers and diluents. They can be included in solidformulations such as powders, granules and pellets comprising carrierssuch as talcum, clay, silicates etc. Liquid preparations comprisediluents, e.g. water and/or solvents such as ethanol, ethyl acetate,glycols, vegetable oils, dimethyl formamide, N-methylpyrrolidone etc.For formulation of the present active compounds conventional additivesand adjuvants can be incorporated into powder, dust and liquidformulations. Examples of such are surface active agents, wettingagents, stabilizers etc. The active compounds of the present inventionare also compatible with other fungicidal agents and agents of otherbiocidal activity, such as insecticides, and can be used in combinationwith such agents if so desired. The concentration of the activesubstance in formulations as above is generally between 1 and 60 percentby weight.

The compounds have shown an excellent effect against fungi of the genusDrechslera, against Septoria nodorum, Ustilago hordei and othercrop-attacking fungi and they can thus advantageously be used asseed-dressing agents.

Although the invention above has been described in the terms of thespecific branched aminoalkanephosphonic acids it falls within the scopeof the invention that fungicidally active salts of the acids are usedfor the control of phytopathogenic fungi in the use as seed-dressingagents or foliar sprays. Salts here refer to metal salts, ammoniumsalts, salts of amines and quaternary ammonium compounds.

Metal salts include e.g. salts of alkali metals, alkaline earth metals,copper, cobalt, zinc, tin and aluminium. Salts of amines include saltsof primary, secondary and tertiary amines, which are aromatic, such ase.g. salts of aniline and alpha-naphtyl-amine, aliphatic orcycloaliphatic containing higher or lower aliphatic groups, and furtherinclude salts of cyclic amines such as e.g. morpholine and pyrrolidineand related compounds. Amines include mono-, di- and polyamines.Quaternary ammonium compounds which can form salts with the branchedaminoalkanephosphonic acids include short chain quaternary compounds,with 1 to 5 carbon atoms, such as e.g. tetramethyl ammonium compoundsand tetrabutyl ammonium compounds, and quaternary ammonium compoundscontaining one or more hydrophobic groups, the other groups being forexample shorter alkyl or hydroxyalkyl groups. These quaternary ammoniumcompounds can for example be alkyl trimethyl ammonium compounds,dimethyl dialkyl ammonium compounds, benzyl dimethyl alkyl ammoniumcompounds, wherein the alkyl chain contains from 6 to 20 carbon atoms,and quaternary ammonium compounds containing corresponding alkylenegroups.

The invention is further illustrated in the following examples which,however, are not intended to limit the same. Parts and percent relate toparts by weight and percent by weight, unless otherwise stated.

EXAMPLE 1 Preparation of 1-Aminopropanephosphonic Acid

Ethyl carbamate (4.45 g), triphenyl phosphite (15.5 g) and propanal(4.06 g) were heated under reflux (1 hour) with acetic acid (10 ml).Concentrated hydrochloric acid (50 ml) was added and the mixture washeated under reflux (6 h) and then allowed to cool. The aqueous phasewas separated, washed with benzene (20 ml) and then evaporated todryness. The residue was dissolved in methanol (40 ml) and propyleneoxide was added until the pH was 6. The crude phosphonic acid wasfiltered off and recrystallised from water/methanol to yield a finewhite crystalline solid (4.2 g, 60.4%) with a melting point of 264°-6°C.

EXAMPLE 2 Preparation of the di-(1-Aminopropanephosphonic Acid) Salt of1,6-Diaminohexane

1-aminopropanephosphonic acid (3.95 g, 284 mmol) and 1,6-diaminohexane(1.65 g, 142 mmol) were dissolved in water (40 ml) and the water wasthen distilled off. Ethanol (50 ml) was then added and also thendistilled off. The residue was dried in a vacuum oven at 50° C. (4 h) toyield the above salt as a fine crystalline solid (5.5 g, 98.2%) with amelting point of 244°-50° C.

EXAMPLE 3 Preparation of the Tetrabutylammonium Salt of1-Aminopropanephosphonic Acid

To 1-aminopropanephosphonic acid (2.91 g, 209 mmol) andtetrabutylammonium bromide (6.74 g, 209 mmol) was added water (50 ml),propylene oxide (20 ml) and water (50 ml). The resultant solution wasthen heated at 50° C. (1/2 h) and allowed to cool. Evaporation of thevolatile components, drying in a vacuum oven at 50° C. (6 h) and furtherdrying over silica gel (4 days) yields the required compound as acolourless, viscous oil (7.5 g, 94.2%).

EXAMPLE 4 Preparation of Copper Salt of 1-Aminopropanephosphonic Acid

1-aminopropanephosphonic acid (5.251 g, 378 mmol) and copper acetatemonohydrate (7.612 g, 378 mmol) were dissolved in water (50 ml) and thewater was distilled off. Water (50 ml) was added to the residue, and thesolid was filtered off, washed with acetone (2×20 ml) and dried in avacuum oven at 60° C. (3 h) to yield the required copper salt as ablue-green powder (6.9 g, 90.2%).

EXAMPLE 5 Preparation of Morpholine Salt of 1-AminopropanephosphonicAcid

1-aminopropanephosphonic acid (4.01 g, 288 mmol) and morpholine (5.02 g,577 mmol) were dissolved in water (20 ml) and ethanol (20 ml) was added.The solvents and excess amine were evaporated off, acetone (50 ml) wasadded and the solid was filtered off, washed with acetone (50 ml) andthen dried in a vacuum oven at 60° C. (4 h) to yield the morpholine saltof 1-aminopropanephosphonic acid (5.5 g, 84.4%) with a melting point of62°-64° C.

Similarly prepared were the salts of the following amines, yield andmelting point are given in brackets.

3-hydroxypropylamine (98.8%, 156°-60° C.)

cyclohexylamine (96.3%, 260°-64° C.)

pyrrolidone (86.5%, 76°-78° C.)

diethylamine (95.5%, 84°-88° C.)

piperazine (87.4%, 98°-108° C.)

hexylamine (94.3%, 266°-68° C.)

N,N-dimethylethanolamine (89.6%, 260°-64° C.)

All the salts prepared according to examples 2 to 5 were characterizedand identified by ¹³ C and ¹ H nuclear magnetic resonance spectroscopy.

EXAMPLE 6

The fungicidal activity of the following compounds was tested:

    ______________________________________                                         ##STR2##                                                                              R.sub.1    R.sub.2                                                   ______________________________________                                         (1)       CH.sub.3     H                                                      (2)       C.sub.2 H.sub.5                                                                            H                                                      (3)       CH(CH.sub.3).sub.2                                                                         H                                                      (4)       C.sub.7 H.sub.15                                                                           H                                                      (5)       CH.sub.3     CH.sub.3                                               (6)       C.sub.2 H.sub.5                                                                            C.sub.2 H.sub.5                                        (7)       CH(CH.sub.3).sub.2                                                                         CH.sub.3                                               (8)       C.sub.3 H.sub.7                                                                            H                                                      (9)       C.sub.4 H.sub.9                                                                            H                                                     (10)       C.sub.5 H.sub.11                                                                           H                                                     (11)       C.sub.2 H.sub.5                                                                            H as potassium salt                                   (12)       C.sub.2 H.sub.5                                                                            H as copper (II) salt                                 ______________________________________                                    

The activity of the substances was examined using a mycelial growthinhibition test on agar according to the following method.

The substances were dissolved in sterilized potato dextrose agar (PDA)to give a concentration of 500 ppm. The mixtures were then poured ontostandard petri dishes of 9 cm diameter. An agar plug (5 mm diameter)with lively growing mycelia (cultivated on PDA) was placed in the centerof each petri dish. After incubation at 28° C. for 1 to 3 weeks,depending on the growth rate of the respective fungus, the growthdiameter was measured and compared with that of untreated dishes.

The effect was tested against Drechslera sativa for some compounds andagainst Drechslera teres for some.

In the table the results are shown by classifying the compoundsaccording to the following scale:

0=0-25% inhibition of growth

1=26-50% inhibition of growth

2=51-75% inhibition of growth

3=76-100% inhibition of growth

                  TABLE                                                           ______________________________________                                               Compound                                                                              Control of D. sativa                                           ______________________________________                                               1       3                                                                     2       3                                                                     3       3                                                                     4       3                                                                     5       3                                                                     6       2                                                                     7       3                                                              ______________________________________                                                       Control of D. teres                                            ______________________________________                                               8       3                                                                     9       3                                                                     10      2                                                                     11      3                                                                     12      2                                                              ______________________________________                                    

In the same manner as described above the effect of some of thecompounds at a dosage of 500 ppm was tested against Fusarium culmorum.The tested compounds were numbers (8), (9) and (10) and they gave acontrol of 3, 3 and 2 respectively.

Also in the same manner some salts of compound 2 were tested againstRhizoctonia solani at a dosage of 300 ppm. The salts were the following:(a) salt of diethyl amine, (b) salt of cyclohexylamine, (c) salt ofmorpholine and (d) salt of pyrrolidine, they all gave a control of 3.

EXAMPLE 7

The effect of some compounds according to the invention againstDrechslera teres was examined by in vivo tests.

The tests were made according to the osmos-method. This method involvesplacing dressed seed on filter papers moistened with a buffered sugarsolution. The filter papers are then placed in covered transparentplastic dishes. The dishes are placed in a thermostat-controlled cabinetwhich maintains a temperature of 22° C. and gives alternating periods of12 hours light and 12 hours darkness.

The examination was carried out after one week. Seed that has survivedshows grown hyphae which form a blot, but the seed has not germinateddue to the osmotic pressure. Seed with living fungi is identified by acolour test. The method is rather severe and all seeds with living fungiare counted, even seed with a very slight infection, which would nothave been seen in a growing plant. The results of the test are given aspercent control, where the infection of untreated seed, for each test,is set to 100%.

The following salts of 1-aminopropanephosphonic acid were tested at adosage of 2 ml aqueous solution (20% active ingredient) per kg seed:

(a) cyclohexylamine salt

(b) hydroxypropylamine salt

(c) morpholine salt

(d) pyrrolidine salt

(e) diethylamine salt

The results were as follows:

(a) 64

(b) 26

(c) 74

(d) 92

(e) 47

EXAMPLE 8

In this example the effect of 1-aminopropanephosphonic acid as a foliarfungicide was examined.

Barley of variety Agneta (6-row barley) was cultivated in standard soilto stage 12 (decimal code for growth stages) during 9 days. The growthclimate was 10000 Lux, lighting for 8 hours and a temperature of between15° and 20° C. Spores of powdery mildew, Erysiphe graminis f. sp. hordeifrom infected plants were shaken over uninfected plants. Incubation wascarried out in a moist-chamber with 100% humidity for 24 hours at 17° C.The plants were then moved back to a green house. Infection started toshow after 5 days and the results were recorded after 8 days.

The test was a preventive test were the plants were sprayed with theactive compound before infection. The plants, 10 for each pot, weresprayed with an aqueous solution containing 500 ppm of theaminophosphonic acid. The solution contained a wetting agent. 6 pots,i.e. 60 plants, were used for the test. As a comparison a commercialproduct (Forbel 750 g a.i./ha) was used in the same manner and acomparison was also made with untreated plants. The number of powderymildew pustles on the plants after the incubation period was counted andthe results were as follows: untreated 14 (=0% effect), treated withsubstance according to the invention 3 (75% effect), treated withcommercial product 0 (=100% effect).

EXAMPLE 9

In these field tests the effect of 1-aminopropanephosphonic acid againsta number of different fungi was tested.

1. Septoria nodorum (Leaf and Glume Blotch)

Material and method: Winter wheat, variety Holme, with a heavy naturalinfection of the fungus S. nodorum was used in the trial. The wheat seedwas weighed and treated with a formulation containing the compound at adosage rate of 2 ml per kg seed (20% active ingredient). Seed-treatmentwas made in a seed-treating machine. The seed was sown in the autumn inrandomised block-design trials (1.3×10 m per plot and 4 replicates).

When the plants had 2-3 leaves the plants were dug up on 2 meters perplot and the attack on the coleoptiles was assessed.

2. Ustilago hordei (Covered Smut of Barley)

Material and method: Barley, variety Birka, was infected with 4 g ofsmut spores per kilo of seed. The barley seed was weighed and treatedwith 2 ml of the formulation (20% active ingredient) per kilo seed. Theseed was sown in the spring in randomised block-design trials.

The number of diseased ears was assessed on an area of 9.4-11.4 squaremeters per plot.

3. Drechslera teres (Net Blotch)

Material and method: Barley seed of the variety Tellus, with a heavynatural infection of the fungus D. teres was utilised in the trials. Theseed was treated as described above and sown in the spring.

At the 2-leaf stage assessment was made of plants with primary attackson the first leaf.

The attacks are given in figures relative to the attacks on untreatedseed (=100% for untreated). The efficacy of the compound is given aspercent control (=0% for untreated) and the results are shown in thetable. When trials were carried out at two different sites, the resultsare given separately.

In further field tests the effect of 1-aminopropanephosphonic acidagainst a number of other fungi was examined.

4. Tilletia caries (Stinking Smut of Winter Wheat)

Material and method: Winter wheat, variety Holme, was infected with 5 gof smut spores per kilo of seed. The wheat seed was weighed and treatedwith 2 ml of the composition (20% active ingredient) per kg seed. Seedtreatment was made in a seed treating machine. The seed was sown inautumn in randomised block-design trials (2 m ×16 m per plot and 4replicates).

The number of diseased ears was counted on area of 10 square meters perplot.

5. Drechslera graminea (Barley Leaf Stripe)

Material and method: Barley seed of the variety Agneta, with a heavynatural infection of the fungus D. graminea was utilised in thesetrials. The seed was treated as described above, with 2 ml compositionper kg seed, and sown in the spring.

At the 5-6 leaf stage (Feekes-Large no. 6, Decimal code no. 31-32) thenumber of diseased plants per square meter was counted.

6. Drechslera avenae (Net Blotch of Oat)

Material and method: Oat seed, variety Selma, with a natural infectionof the fungus D. avenae was utilised in these trials. The seed wastreated at a dosage rate of 2 ml per kg seed (20% a.i.).

At the 2-leaf stage the number of diseased plants per square meter wascounted.

7. Ustilago avenae (Loose Smut of Oat)

Material and method: Oat seed, variety Hedvig, was infected with 3 g ofsmut spores per 3 liters of water (wet-infection with vacuum). Theinfected seed was dried in thin layers in room temperature, until thewater content was about 15%. The dry, infected seed was treated with 2ml of the composition (20% a.i.) per kg seed in a seed-dressing machine.

The treated seed was sown in spring in randomised block-design trials(1.35 m ×8 m per plot and 4 replicates). The number of diseased ears wascounted and the result given as the number per 3 square meters.

The results for these field trials are given in the table in the samemanner as stated earlier.

                  TABLE                                                           ______________________________________                                        Fungus            Attack  Control                                             ______________________________________                                        Septoria nodorum  27      73                                                  Treated                                                                       Ustilago hordei                                                               Trial site I      22      78                                                  Treated                                                                       Trial site II     28      72                                                  Treated                                                                       Drechslera teres                                                              Trial site I      0       100                                                 Treated                                                                       Trial site II     0.3     99.7                                                Treated                                                                       Tilletia caries   18      82                                                  Treated                                                                       Drechslera graminea                                                           Trial site 1      4       96                                                  Treated                                                                       Trial site II     1       99                                                  Treated                                                                       Drechslera avenae                                                             Trial site I      0       100                                                 Treated                                                                       Trial site II     1       99                                                  Treated                                                                       Ustilago avenae                                                               Trial site I      4       96                                                  Treated                                                                       Trial site II     5       95                                                  Treated                                                                       ______________________________________                                    

In field tests, as above, the effect of a straight chainaminoalkanephosphonic acid with the same number of carbon atoms,3-aminopropanephosphonic acid, against Drechslera teres and Drechsleraavenae was examined as a comparison. The control of infection obtainedby this compound was 28 and 37 percent respectively.

EXAMPLE 10

The effect of salts of 1-aminopropanephosphonic acid against D. graminaewas investigated and the test was carried out as follows:

Seed treated with the salts, in aqueous formulations at a dosage of 0.4g a.i. per kg seed, were sown in dishes containing moist earth mixedwith gravel. The dishes were kept in a cold place (+6° C.) for 10 to 12days. They were then kept at room temperature and illuminated until theyhad reached the 2-3 leaves stage. The test was then evaluated. Thenumber of germinated plants and plants with characteristic spots oncoleoptile, leaves and roots respectively were counted. The percentattack for each treatment is compared with that for untreated seed. Theattack for untreated seed is set to 100% and the seed dressing effectgiven below is in percent relative to this:

Salt of 1-Aminopropanephosphonic Acid/% Effect

(a) potassium salt, 97%

(b) copper (II) salt, 98%

(c) cyclohexylamine salt, 100%

(d) 3-hydroxypropylamine salt, 100%

(e) piperazine salt (bis-acid salt of piperazine), 98%

(f) hexamethylenediamine salt (bis-acid salt), 100%

(g) hexylamine salt, 98%

(h) dimethyl ethanolamine salt, 100%

Similarly the effect of several salts against Septoria nodorum wasinvestigated. Seeds treated with the salts, in aqueous formulations at adosage of 0.4 g a.i. per kg seed, were sown in soil contained in bowlsof 20 cm diameter (50 kernels/bowl). The bowls were then kept in agrowing chamber at +6° C. for 10 to 12 days and then moved into aclimate cabinet. The conditions in the climate cabinet were: temperature20° C. in the day, 10° to 13° C. at night with a 16 h day and an 8 hnight. The disease was assessed when the plants had reached the 21/2leaf stage. The level of disease was compared to a control, whose levelof infection was set to 100%.

SALT OF 1-Aminopropanephosphonic Acid/% Effect

(a) potassium salt, 100%

(b) copper salt, 94%

(c) diethylamine salt, 100%

(d) cyclohexylamine salt, 100%

(e) morpholine salt, 94%

(f) pyrrolidine salt, 100%

(g) piperazine salt (bis-acid salt), 100%

(h) hexamethylenediamine salt (bis-acid salt), 100%

(i) hexylamine salt, 94%

(j) 2-aminobutane salt, 100%

(h) isopropylamine salt, 94%

(l) tetrabutylammonium salt, 94%

(m) hydrochloric acid addition salt, 100%

EXAMPLE 11

In this test of comparison was made between the diethylbetaaminoethylphosphonate according to the U.S. Pat. No. 3,764,677(Kerst) and 1-aminopropanephosphonic acid. The tests were made accordingto the osmos-method as described in Example 7. The effect of thecompounds were tested against Drechslera teres at adosage of 0.4 ga.i./kg of seed.

The diethyl betaaminoethylphosphonate gave an effect of 3%, while the1-aminopropanephosphonic acid according to the present invention gave aneffect of 50%.

EXAMPLE 12

The following salts of 1-aminopropanephosphonic acid were evaluated infield trials against a number of different fungi:

Salt (a)=monopotassium salt

Salt (b)=copper salt

Salt (c)=hexamethylene diamine salt (bis-acid salt)

Salt (d)=isopropylamine salt

Salt (e)=2-aminobutane salt

The methods for treatment of seed and evaluation of effect were inaccordance with those disclosed in Example 9 for the respective types ofseeds and fungi. Variety of seed and dosage were as set out below. Allseed treatments were made with aqueous formulations of the salts.

1. Drechslera teres (Net Blotch on Barley)

Barley seed of the variety Gunilla. Dosage 200 ml per 100 kg seed offormulations containing 150 g a.i. per liter.

2. Drechslera graminae (Barley Leaf Stripe)

Barley seed of the variety Agneta Dosage 200 ml per 100 kg seed offormulations containing 150 g a.i. per liter.

3. Drechslera avenae (Net Blotch of Oat)

Oat seed of the variety WW 17064. Dosage 300 ml per 100 kg seed offormulations containing 150 g a.i. per liter.

4. Ustilago avenae (Loose Smut of Oat)

Oat seed of the variety Sang, infected with 0.75 g of smut spores perliter of water. Dosage 300 ml per 100 kg seed with formulationscontaining 150 g a.i. per liter.

In the table below the results are, as in Example 9, set out as %control in reference to the comparison with untreated seed in each testfor which the percent control is 0.

                  TABLE                                                           ______________________________________                                        Fungus      Seed Treating Agent                                                                          % Control                                          ______________________________________                                        D. Teres    Salt a)        100                                                "           Salt (b)       100                                                "           Salt (c)       100                                                "           Salt (d)       100                                                "           Salt (e)       100                                                D. graminge Salt (a)       97                                                 "           Salt (b)       95                                                 "           Salt (c)       97                                                 "           Salt (d)       97                                                 "           Salt (e)       98                                                 D. avenae   Salt (a)       99                                                 "           Salt (b)       97                                                 "           Salt (c)       99                                                 "           Salt (d)       99                                                 "           Salt (e)       100                                                U. avenae   Salt (a)       79                                                 "           Salt (b)       78                                                 "           Salt (c)       82                                                 "           Salt (d)       83                                                 "           Salt (e)       81                                                 ______________________________________                                    

We claim:
 1. A method for controlling phytopathogenic fungi which methodcomprises applying to infected or infectable seed or foliage afungicidally effective amount of an aminoalkanephosphonic acid of theformula ##STR3## wherein R₁ is an alkyl group having 1 to 12 carbonatoms and R₂ is hydrogen or an alkyl group having 1 to 12 carbon atoms,or fungicidially effective salts or acid addition salts of theaminoalkanephosphonic acids.
 2. A method according to claim 1, whereinR₂ is hydrogen.
 3. A method according to claim 1, wherein the compoundsare used as seed-treating agents.
 4. A method for controllingphytopathogenic fungi according to claim 1, wherein1-aminopropanephosphonic acid, or fungicidally effective salts or acidaddition salts of 1-aminopropanephosphonic acid, are used.
 5. A methodaccording to claim 4, wherein the compounds are used as seed-treatingagents.
 6. A method according to claim 1, wherein R₁ is an alkyl grouphaving 1 to 5 carbon atoms.
 7. A method for controlling phytopathogenicfungi, which method comprises applying to infected or infectable seed asa seed dressing agent or to infected or infectable foliage as foliarspray a fungicidally effective amount of an aminoalkanephosphonic acidof the formula ##STR4## wherein n is 0 or 1, R₁ is an alkyl group having1 to 12 carbon atoms, and R₂ is hydrogen or an alkyl group having 1 to12 carbon atoms, and wherein when n is 1, R₂ is hydrogen, orfungicidally effective salts of the aminoalkanephosphonic acids.
 8. Amethod according to claim 7, wherein R₂ is hydrogen.
 9. A methodaccording to claim 7, wherein R₁ is an alkyl group having 1 to 5 carbonatoms.
 10. A method according to claim 7, wherein the compounds are usedas seed-treating agents.
 11. A method for controlling phytopathogenicfungi which method comprises applying to infected or infectable seed asa seed dressing agent or to infected or infectable foliage afungicidally effective amount of an aminoalkanephosphonic acid of theformula ##STR5## or fungicidally effective salts of thisaminopropanephosphonic acid.
 12. A method for controllingphytopathogenic fungi according to claim 11, wherein the salt of theaminopropanephosphonic acid is the potassium salt.
 13. A method forcontrolling phytopathogenic fungi according to claim 11, wherein thecompounds are used as seed-dressing agents.
 14. A method for controllingphytopathogenic fungi according to claim 12, wherein the compounds areused as seed-dressing agents.
 15. A method for controllingphytopathogenic fungi on a cereal selected from wheat, barley and oat,which method comprises applying to seed as a seed dressing agent or tofoliage of said cereal a fungicidally effective amount of anaminoalkanephosphonic acid of the formula ##STR6## wherein n is 0 or 1,R₁ is an alkyl group having 1 to 12 carbon atoms, and R₂ is hydrogen oran alkyl group having 1 to 12 carbon atoms, and wherein when n is 1, R₂is hydrogen, or fungicidally effective salts of theaminoalkanephosphonic acids.
 16. A method according to claim 15, whereinR₂ is hydrogen.
 17. A method according to claim 15, wherein R₁ is analkyl group having 1 to 5 carbon atoms.
 18. A method according to claim15, wherein the compounds are used as seed-dressing agents.
 19. A methodfor controlling phytopathogenic fungi on a cereal selected from wheat,barley and oat, which method comprises applying to seed as aseed-dressing agent or to foliage of said cereal a fungicidallyeffective amount of an aminoalkanephosphonic acid of the formula##STR7## wherein R₁ is an alkyl group having 1 to 12 carbon atoms and R₂is hydrogen or an alkyl group having 1 to 12 carbon atoms, orfungicidally effective salts of the aminoalkanephosphonic acids.
 20. Amethod according to claim 19, wherein R₂ is hydrogen.
 21. A methodaccording to claim 19, wherein R₁ is an alkyl group having 1 to 5 carbonatoms.
 22. A method for controlling phytopathogenic fungi according toclaim 19, wherein the compounds are used as seed-dressing agents.
 23. Amethod according to claim 19, wherein 1-aminopropanephosphonic acid, orfungicide effective salts of 1-aminopropanephosphonic acid, are used.24. A method according to claim 23, wherein the compounds are used asseed-treating agents.